Minimally invasive robotic surgical or telesurgical systems have been developed to increase a surgeon's dexterity and to avoid some of the limitations on traditional minimally invasive techniques. In telesurgery, the surgeon uses some form of remote control, e.g., a servomechanism or the like, to manipulate surgical instrument movements, rather than directly holding and moving the instruments by hand. In telesurgery systems, the surgeon can be provided with an image of the surgical site at the surgical workstation. While viewing a two or three dimensional image of the surgical site on a display, the surgeon performs the surgical procedures on the patient by manipulating master control devices, which in turn control motion of the servomechanically operated instruments.
In robotically assisted surgery, the surgeon typically operates a master controller to control the motion of surgical instruments at the surgical site from a location that may be remote from the patient (e.g., across the operating room, in a different room, or a completely different building from the patient). The master controller usually includes one or more hand input devices, such as hand-held wrist gimbals, joysticks, exoskeletal gloves or the like, which are operatively coupled to the surgical instruments that are releasably coupled to a patient side surgical manipulator (“the slave”). The master controller controls the instruments' position, orientation, and articulation at the surgical site. The slave is an electro-mechanical assembly that includes a plurality of arms, joints, linkages, servo-motors, etc. that are connected together to support and control the surgical instruments. In a surgical procedure, the surgical instruments (including an endoscope) may be introduced directly into an open surgical site or more typically through trocar sleeves into a body cavity. Depending on a surgical procedure, there are available a variety of surgical instruments, such as tissue graspers, needle drivers, electrosurgical cautery probes, etc., to perform various functions for the surgeon, e.g., holding or driving a needle, suturing, grasping a blood vessel, or dissecting, cauterizing or coagulating tissue.
A surgical manipulator assembly may be said to be divided into three main components that include a non-sterile drive and control component, a sterilizable end effector or surgical tool/instrument, and an intermediate connector component. The intermediate connector component includes mechanical elements for coupling the surgical tool with the drive and control component, and for transferring motion from the drive component to the surgical tool. Electrical cables, such as flexible flat cables, have been previously used to provide power, ground, and/or data signals between the components of the surgical system. Prior telerobotic surgical systems with such electrical cables are described for example in U.S. application Ser. No. 11/613,800 filed Dec. 20, 2006, entitled “Telescopic Insertion Axis Of A Robotic Surgical System”, the complete disclosure of which has been previously incorporated herein by reference for all purposes. However, issues related to small clearances, electrical noise, mechanical fatigue, and mechanical hazards can possibly lead to malfunction and decreased system robustness. Furthermore, power and data transactions for electrical circuits must cross a sterile barrier (e.g., a membrane or film) that separates the sterile field containing surgical activity from the non-sterile mechanisms of the surgical robot.
What is needed, therefore, are improved apparatus and methods for providing electrical signals and/or power through a sterile barrier in a telerobotic surgical system to surgical instruments in the sterile field.